1 files changed, 103 insertions, 14 deletions

diff --git a/include/linux/genhd.h b/include/linux/genhd.h
index 5f2f4c4d8fb0..300d7582006e 100644
--- a/include/linux/genhd.h
+++ b/include/linux/genhd.h
@@ -12,6 +12,7 @@
 #include <linux/types.h>
 #include <linux/kdev_t.h>
 #include <linux/rcupdate.h>
+#include <linux/slab.h>
 
 #ifdef CONFIG_BLOCK
 
@@ -86,7 +87,15 @@ struct disk_stats {
         unsigned long io_ticks;
         unsigned long time_in_queue;
 };
-        
+
+#define PARTITION_META_INFO_VOLNAMELTH  64
+#define PARTITION_META_INFO_UUIDLTH     16
+
+struct partition_meta_info {
+        u8 uuid[PARTITION_META_INFO_UUIDLTH];   /* always big endian */
+        u8 volname[PARTITION_META_INFO_VOLNAMELTH];
+};
+
 struct hd_struct {
         sector_t start_sect;
         sector_t nr_sects;
@@ -95,16 +104,18 @@ struct hd_struct {
         struct device __dev;
         struct kobject *holder_dir;
         int policy, partno;
+        struct partition_meta_info *info;
 #ifdef CONFIG_FAIL_MAKE_REQUEST
         int make_it_fail;
 #endif
         unsigned long stamp;
-        int in_flight[2];
+        atomic_t in_flight[2];
 #ifdef  CONFIG_SMP
         struct disk_stats __percpu *dkstats;
 #else
         struct disk_stats dkstats;
 #endif
+        atomic_t ref;
         struct rcu_head rcu_head;
 };
 
@@ -116,6 +127,12 @@ struct hd_struct {
 #define GENHD_FL_SUPPRESS_PARTITION_INFO        32
 #define GENHD_FL_EXT_DEVT                       64 /* allow extended devt */
 #define GENHD_FL_NATIVE_CAPACITY                128
+#define GENHD_FL_BLOCK_EVENTS_ON_EXCL_WRITE     256
+
+enum {
+        DISK_EVENT_MEDIA_CHANGE                 = 1 << 0, /* media changed */
+        DISK_EVENT_EJECT_REQUEST                = 1 << 1, /* eject requested */
+};
 
 #define BLK_SCSI_MAX_CMDS       (256)
 #define BLK_SCSI_CMD_PER_LONG   (BLK_SCSI_MAX_CMDS / (sizeof(long) * 8))
@@ -129,10 +146,12 @@ struct blk_scsi_cmd_filter {
 struct disk_part_tbl {
         struct rcu_head rcu_head;
         int len;
-        struct hd_struct *last_lookup;
-        struct hd_struct *part[];
+        struct hd_struct __rcu *last_lookup;
+        struct hd_struct __rcu *part[];
 };
 
+struct disk_events;
+
 struct gendisk {
         /* major, first_minor and minors are input parameters only,
          * don't use directly.  Use disk_devt() and disk_max_parts().
@@ -144,12 +163,16 @@ struct gendisk {
 
         char disk_name[DISK_NAME_LEN];  /* name of major driver */
         char *(*devnode)(struct gendisk *gd, mode_t *mode);
+
+        unsigned int events;            /* supported events */
+        unsigned int async_events;      /* async events, subset of all */
+
         /* Array of pointers to partitions indexed by partno.
          * Protected with matching bdev lock but stat and other
          * non-critical accesses use RCU.  Always access through
          * helpers.
          */
-        struct disk_part_tbl *part_tbl;
+        struct disk_part_tbl __rcu *part_tbl;
         struct hd_struct part0;
 
         const struct block_device_operations *fops;
@@ -161,9 +184,8 @@ struct gendisk {
         struct kobject *slave_dir;
 
         struct timer_rand_state *random;
-
         atomic_t sync_io;               /* RAID */
-        struct work_struct async_notify;
+        struct disk_events *ev;
 #ifdef  CONFIG_BLK_DEV_INTEGRITY
         struct blk_integrity *integrity;
 #endif
@@ -181,6 +203,30 @@ static inline struct gendisk *part_to_disk(struct hd_struct *part)
         return NULL;
 }
 
+static inline void part_pack_uuid(const u8 *uuid_str, u8 *to)
+{
+        int i;
+        for (i = 0; i < 16; ++i) {
+                *to++ = (hex_to_bin(*uuid_str) << 4) |
+                        (hex_to_bin(*(uuid_str + 1)));
+                uuid_str += 2;
+                switch (i) {
+                case 3:
+                case 5:
+                case 7:
+                case 9:
+                        uuid_str++;
+                        continue;
+                }
+        }
+}
+
+static inline char *part_unpack_uuid(const u8 *uuid, char *out)
+{
+        sprintf(out, "%pU", uuid);
+        return out;
+}
+
 static inline int disk_max_parts(struct gendisk *disk)
 {
         if (disk->flags & GENHD_FL_EXT_DEVT)
@@ -325,21 +371,34 @@ static inline void free_part_stats(struct hd_struct *part)
 
 static inline void part_inc_in_flight(struct hd_struct *part, int rw)
 {
-        part->in_flight[rw]++;
+        atomic_inc(&part->in_flight[rw]);
         if (part->partno)
-                part_to_disk(part)->part0.in_flight[rw]++;
+                atomic_inc(&part_to_disk(part)->part0.in_flight[rw]);
 }
 
 static inline void part_dec_in_flight(struct hd_struct *part, int rw)
 {
-        part->in_flight[rw]--;
+        atomic_dec(&part->in_flight[rw]);
         if (part->partno)
-                part_to_disk(part)->part0.in_flight[rw]--;
+                atomic_dec(&part_to_disk(part)->part0.in_flight[rw]);
 }
 
 static inline int part_in_flight(struct hd_struct *part)
 {
-        return part->in_flight[0] + part->in_flight[1];
+        return atomic_read(&part->in_flight[0]) + atomic_read(&part->in_flight[1]);
+}
+
+static inline struct partition_meta_info *alloc_part_info(struct gendisk *disk)
+{
+        if (disk)
+                return kzalloc_node(sizeof(struct partition_meta_info),
+                                    GFP_KERNEL, disk->node_id);
+        return kzalloc(sizeof(struct partition_meta_info), GFP_KERNEL);
+}
+
+static inline void free_part_info(struct hd_struct *part)
+{
+        kfree(part->info);
 }
 
 /* block/blk-core.c */
@@ -348,7 +407,6 @@ extern void part_round_stats(int cpu, struct hd_struct *part);
 /* block/genhd.c */
 extern void add_disk(struct gendisk *disk);
 extern void del_gendisk(struct gendisk *gp);
-extern void unlink_gendisk(struct gendisk *gp);
 extern struct gendisk *get_gendisk(dev_t dev, int *partno);
 extern struct block_device *bdget_disk(struct gendisk *disk, int partno);
 
@@ -360,6 +418,11 @@ static inline int get_disk_ro(struct gendisk *disk)
         return disk->part0.policy;
 }
 
+extern void disk_block_events(struct gendisk *disk);
+extern void disk_unblock_events(struct gendisk *disk);
+extern void disk_check_events(struct gendisk *disk);
+extern unsigned int disk_clear_events(struct gendisk *disk, unsigned int mask);
+
 /* drivers/char/random.c */
 extern void add_disk_randomness(struct gendisk *disk);
 extern void rand_initialize_disk(struct gendisk *disk);
@@ -533,7 +596,10 @@ extern int disk_expand_part_tbl(struct gendisk *disk, int target);
 extern int rescan_partitions(struct gendisk *disk, struct block_device *bdev);
 extern struct hd_struct * __must_check add_partition(struct gendisk *disk,
                                                      int partno, sector_t start,
-                                                     sector_t len, int flags);
+                                                     sector_t len, int flags,
+                                                     struct partition_meta_info
+                                                       *info);
+extern void __delete_partition(struct hd_struct *);
 extern void delete_partition(struct gendisk *, int);
 extern void printk_all_partitions(void);
 
@@ -562,6 +628,29 @@ extern ssize_t part_fail_store(struct device *dev,
                                const char *buf, size_t count);
 #endif /* CONFIG_FAIL_MAKE_REQUEST */
 
+static inline void hd_ref_init(struct hd_struct *part)
+{
+        atomic_set(&part->ref, 1);
+        smp_mb();
+}
+
+static inline void hd_struct_get(struct hd_struct *part)
+{
+        atomic_inc(&part->ref);
+        smp_mb__after_atomic_inc();
+}
+
+static inline int hd_struct_try_get(struct hd_struct *part)
+{
+        return atomic_inc_not_zero(&part->ref);
+}
+
+static inline void hd_struct_put(struct hd_struct *part)
+{
+        if (atomic_dec_and_test(&part->ref))
+                __delete_partition(part);
+}
+
 #else /* CONFIG_BLOCK */
 
 static inline void printk_all_partitions(void) { }